Two-cycle internal-combuwstion engine



June 28, 1927. L. V. HSFORD ET AL 1,633,585

TWO-CYCLE INTERNAL GOMBUSTION ENGINE Filed Dec- 19. 1924 4 Sheets-Sheet 1 lNyENTOR .Hier/.san L Khosfard- BY W" ATTORNEY June 28, 1927.

l.. v. HOsFoRD ET AL- Two-cYcLE INTERNAL coNusTIoN ENGINE Filed Deo 19. 1924 4 Sheets-Sheet 2 Has/ordi MW 1927. June 28' L. v. HosFoRD ET AL TWO-CYCLE INTERNAL COMBUSI'ION ENGINE 4 sheets-sheet 3 Filed Dec. 19, 1923 ATTORNEY 1,633,585 June 28 1927 l.. v. HosFoRD ET AL TWO-CYCLE b.INTERNAL COMBUSTION ENGINE Filed Dec. 19. 1924 4 Sheets-Sheet 4 i9; l 5?@ 5m .Da-lilxNvgNTOR u. 7er/san.

lj.. l( Hosfofd.

BY X

ATTORNEY iti Patented June 28, 1927.

UNTED STATES PATENT OFFICE.

LEONARD V. HOSFORD AND DAVID DAVISON, OF PORTLAND, OREGON, ASSIGNORS, BY

MESNE ASSIGNMENTS, TO OF OREGON.

HOSFOR-D LIOTOR CONSTRUCTION CO., .A CORPORATION TWO-CYCLE INTERNAL-COMBUSTION ENGINE.

Application filed December @or pr nt iuvcnton modification of that disclosed in our co-pending application tiled iiieptember 30, 1924, Serial No. 740,848 and it particuh ly has for its object to prii-dc a :nodi ed construction of the cylinder hind, to reduce the number of valves carried thereby, and to make it possible for the utiiif/.alion in the cylinder head of but a single valve for air scavenging, air starting compression release purposes.

1n carrying out our present invention we provide a supplemental piston valve mechanism cooperatively connecte-d with the source of the compressed air supply (used for start- U purposes) and with the by-pass duct of the engine and .ro cri-ordinate it with the operative mechanism for the fuel and scavenging valves, in the cylinder head as to enable the several mechanisms lo perform their functions at proper and desired times.

ln its more specific nature the invention resides in 'those novel structures, combinations .and arrangements of parts, all of which will be first ful ly described, and then be specifically pointed out in the appended clainis, reference being had to the accompanying f lrawings, in Which:-

Figure 1 is a plan view of a single engine unit employing the invention.

liigure 2 is u vertical section on the line 2 of Figure l.

Figure 3 is a vertical 3-3 of Figure 1. I

Figure t is an end elevation of the same.

iiigures 5, G and 7 are diagrammatic views of th:` supplemental piston valve.

Figure 8 is an inverted plan of the cylin der hond.

Figure 9 a horizontal section thereof on the line 9-9 of Figure 2.

Figures 10 and 11 are detail views slip clutch hereinafter referred to.

Figure 12 is a front elevation, parts being in section, of the invention.

Referring now to the accompanying drawings, in which like numerals of reference indicate like parts in all the figures, 1 represents the bed which also constitutes the lower part of the crank case, 2 th-e upper part of the crank case, 3 the Working cylinder, 4 the cylinder head, the Water cooling exhaust duct, 6 the reciprocating piston, 7 the stationary piston, 8 the connecting rod, 9 the Wrist pin and the crank shaft; the

l ii S' section on the .line

of the 19, 1924. Serial N0. 757,064.

general construction of all of which parts, except the cylinder head, may be substantially that of our co-pending application above referred to.

The cylinder head is provided With a long narrow compression chamber 11 into one end of which and in the direction of the length of the chamber and in a horizontal direction the fuel inlet valve is designed at proper times to inject a charge of fuel oil in an atoinized state through the fuel inlet valve port 12. 13 represents the governor which controls the operation of the engine, and as the construction of this governor may he of any approved type, such for instance as dcscribed in our co-pending application aforesaid, a detail description and illustration thereof is thought to be unnecessary, since no claim to the 0overnor per se is made in this application.

The reciprocating piston is provided With a concave-convex head 14 and thc Working cylinder 3 is secured to the crank case 2 by blots 15, while the stationary piston is secured to the working cylinder by similar bolts 15. i

The cylinder 3 is provided with vertical recesses 16 for the Wrist pin bosses to ride in. 17 is the by-pass inlet port, 18 the hypass duct of the cylinder, 19 the by-pass duct of the cylinder head Which delivers into the scavenging air valve chamber 2() of the cylinder head and from Which the airis in turn delivered into the Working chamber'. 21 is the valve seat for the scavenging valve and 22 the exhaust ports leading' to the Water cooled exhaust duct.

The cylinder 3 is recessed at 23 for the flange 24 of the stationary piston 7 as to insure proper alignment of these parts. 25 4esignates the slots in the stationary piston through which the Wrist pin bosses project. The stationary piston is provided With air ports 26 of grid construction in its head Which are controlled by a grid valve 27, the latter having ports 28 and being mounted on a stud or bolt 29.

31 is the Water jacket space of the cylinder head in which cooling Water is circulated for the usual purposes and in the usual manner. 32 designates the combined scavenging and air-starter valve which has a guide 33 and is held seated by a return spring 311.r It is opened by a rocker arm v35 mounted on a suitable bearing support 36 and itself operated in the manner presently explained.

37 is the fuel valve casing, 38 the fuel valve stem which is adapted to be engaged by the rocker arm 39 mounted on a bearing 40 and operated by a pull rod 41 that is in turn actuated by a camming lever 42,Athe roller 43 of which is adapted to cooperate with the cam 45 on the counterweight 44.

46 is a control shaft which has an eccentric stub 48 on which the governor actuated lever 47 having an eccentric bearing 47 is mounted. 49 is a lever and quadrant for effecting the changes in position of the shaft 46. 50 represents the slip clutch on the control shaft 46 for manipulating the scavenging air valve at times. A camming lever 51 operates the fuel pump 54 and the scavenging valve through the action of a cam 52 on one of the counterweights of the crank shaft, the camming lever 51 Abeing mounted on a bearing 53 on the shaft 46.

The fuel pump 54 includes a governor operated controlling lever 55 which is connected by connections 56 to the governor lever 57, the latter operating both the fuel pump governor-operated lever and the governor actuated lever 47. 58 is a governor actionregulat-ing lever for causing the tension of the governor spring to be increased or diminished and the actionof the governor thereby varied to suit the yrequirements desired.

59 is a piston valve casing and support which has a compres-sed air inlet port E'60 and a port 62 which connects with a duct 61 from the by-pass duct 18. 63 is -a piston operating within the casingl 59, and having an open ended chamber 64. Y The piston also has a lower port 65 for port 62 at times. 66 is the-upper Apiston chamber which has an outlet port 68.' A return spring 69 tends to hold the piston against `the action of the camming lever. v u

7() is the piston (rod which connects the piston with the camming lever 71 that is mounted by an eccentric bearing. 72 on an eccentric 73 on theY control shaft 46.

74 is a duplex roller-carrying lever to Vcooperate with the separate? cam elements on the counterweight on'thecranlr shaft. These elements are designated as follows: one lcam having a high part 75 and a low :part 77 and the other having a high part 76- and a low part 78. f

79 is the reversing' shaft which is connected .by a link 80 to -the'leverv74 'so that by shifting the shaft .79 onefioranother of the rollers of the duplex -roller-cazriying lever 74 may be brought into relation with its particular cam lso as properly Jto-time lthe action according fas the yengineis tofirun in one dinectio'n or another. v 4

The construction and operation of the registering with the inlet "port 67 and an fuel pump mechanism in the presentinstance may be that disclosed in our co-pending application above referred to and as its specilic construction per se forms no part of the present invention detailed illustration and description of which is thought to be unnecessary.

So far as described ldie manner iii which the engine operates as explained is as follows lV ith the engine at rest and it is desired to start it up under the action of the compressed air which is stored in any suitable reservoir (not shown) and conveyed by a suitable duct (not shown) to the port 60 of u the piston valve mechanism, the attendant manipulates the control shaft 46 in such way that the cams will raise the camming lever that operates the fuel valve out of the range of influence of its cam so as to render the fuel valve inactive for the time being. The same operation of the control shaft causes the camming lever of the fuel pump and scavenging valve to move the scavenging Valve to the open or unseated position. I'lhe :s

same movement of the control shaft and lever brings one or the other of the cam engaging rollers of the duplex carrying lever 74 into the path of action of its particular cam on the balance weight of the fly wheel. af.'

During the period of air starting the scavenging valve in the cylinder head remains open and the air for starting purposes is admitted through the duct 61 directly into the by-pass duct of the engine cylinder.

When the cam engaging roller of the lever 7 4 is in the highest position, i. e. in engagement with the highest cammed portion of the ccunterweight, the ports 60 and 62 will be in communication via the ports 67, chamber 60 and port 68 to permit compressed air to enter the by-pass duct, to How through the cylinder head into the working chamber of the engine cylinder. At the time, of course, when the port 62 is uncovered the reciprocating piston Will have reached the top of its stroke and begun its downward travel under the influence of the now admitted compressed air. VJhen the cam has travelled through an arc of ninety degrees the roller will have dropped down onto the reduced portion 77 or 78 as the case may be, of that cam 75 or 76 as the case may be, and the ports 60 and 62 will have been closed olf. At this time the parts which were formerly7 in the position shown in Figure 5 have -movled to the position shown in Figure 6.

.chamber through the cylinder head by-pass duct7 the cylinder by-pass duct and the internal chamber (34 of the valve G3 to atmosphere, which prevents the piston on its upstroke compressing the air within the working chamber.

As soon as the engine has developed Suthcient momentum thl attendantagain shifts the shalt 46 to the normal running position, i. e., that position at which the rocker arm Tl will be li fled to the non-operative position and the rocker arms for the scavenging and fuel valves will be restored to thei1 operative positions, whereupon the operation ot the engine results in the reciprocating pis ton drawing a charge of fresh air into it through the grid valve of the stationary cylinder while compressing a previous charge of air in the working chamber, then as it :tarts down on its working stroke the fuel valve opens to inject a spray of fuel into the cylinder head combustion chamber where it becomes instantly ignited by the tempera` ture ot the highly compressed air and impels the piston downwardly on its working' stroke. The interval during which the fuel valve is allowed to remain open is approximately thirty-six degrees, after which the remaining movement of the reciprocating piston is under the expansion of the burnt mixture. As the working' piston moves downwardly it compresses the fresh air with in it until the port of the piston registers with the by-pass inlet port, whereupon the compressed fresh air is blown into the by-pass duct and when the scavenging valve is open (and this occurs is soon as the piston une: vers the exhaust ports) the fresh air will be blown through the cylinder head into the working chamber and expel any burnt residue therein, such fresh air charge then being compressed on the next compres` ,f ion stroke of th,`l piston as before.

'lhe fuel pump operation and its control and the governor operation and control of the fuel valve, etc. being the same as that disclosed in our eo-pending application aforesaid and per se forming in their specific structures no part of the present invention, a detailed description of their construction and operation in this application is thought to be superfluous.

rl`he slip clutch is so designed that the jaws of the clutch are permitted to slip through a dis-tance of thirty degrees or more, thus accomplishing the unseating of the scavenging valve during the starting opera tion as before referred to.

W'hen the engine is running under power impulses the piston valve 63 remains in the position indicated in Figure 6, thereby preventing the escape of scavenging air.

From the foregoing description, taken in connection with the accompanying drawings, it is thought the complete construction, operation and advantages of the invention will be clear to those skilled in the art, and We desire it understood that changes in the details of construction, the proportioning of parts and arrangement thereof may be made without departing from the spirit of the in vention or the scopo ot' the appended claims.

Vhat we claim is:

1. In two cycle internal combustion engines having piston controlled exhaust and by-pass ports and ducts, a c vlinder head having a centrally located air port with a valve seat and having a compression space, a scavenging valve in said head to deliver air from the by-pass into the working chamber, means causing the working piston to draw a fresh air charge into itself on one stroke and deliver it com ressed to the bypass duct on another stroke and again compressing the air in the working chamber, a i'uel valve on the head for injecting fuel crosswise of the head into the compressed air Within the compression space of the engine, andan auxiliary valve connected with the by-pass duct for delivering compressed starting air at times.

2. ln two cycle internal combustion engines having piston controlled exhaust and bypass por's and ducts. a cylinder head, a warenging valve in said head to deliver air from the by-pass into the working chamber, means causing the working piston to draw a fresh air charge into itself on one stroke and deliver it compressed to the by-pass lduct on another stroke and again compressing the air in the working chamber, a fuel valve on the head for injecting fuel into the conlpressed air within the compression space of thc engine. and an auxiliary valve connected with the ily-pass duct for delivering cornpiesled starting air at times, means to operate said fuel and scavenging valves and said auxiliary valve, and means to render said fuel and scavenging valves non-operativex while said auxiliary valve is operative and vice versa.

lfn two c vcle internal combustion enics wherein is provided a cylinder and head having b v-pass ducts and ports, said cylinder having an exhaust port, a working piston Controlling said ports, a scavenging valve and a fuel injection valve; an auxiliary piston valve mechanism and mechanical means to operate the same, said auxiliar valve mechanism having an inlet port to receive compressed starting air and having a delivery port for delivering the same to the lav-pass duct. and having passages to atmosphere. a valve piston controlling said noi-ts of thi` auxiliary valve mechanism for the purpose of altcrnatingly admitting compresse/.l starting air into said bypass duct to impel the working piston and exhausting air from the b v-pass duct to relieve compression.

4l. In internal combustion engines of the character stated, a cylinder head having a long narrow Compression space of shallow depth, means to inject fuel oil horizontally in ene end of said space toward the other end, said compression space being centrally eulargedr` said head having an air duct to the enlarged space which is ctmtirolled by a valve carried by the cylinder head for the purpose of admitting compressed air into the eonr pression space from the top, substantially as shown and described.

In two cycle Diesel engines of the ported cylinder type, piston controllingmeans to seavenge the working chamber with air after each working stroke of the piston, said means including a scavenging valve and a duct leadingl thereto, means to inject a .spray of fuel oil into the compression space ot' the engine after the scavenging air is compressed therein by the piston, and means associated with the aforesaid parts for operating the engine under compressed air for starting purposes.

t5. In two Cycle Diesel engines of the ported (cylinder type, piston controlling means to scavenge the working chamber with air after each working stroke of the piston, said means including a scavenging valve and a duct leading thereto, means to inject. a spra v of fuel oil into the compression space of the engine after the scavenging air is compressed therein by the piston, and means associated with the, aforesaid parts for operating the engine under compressed air for starting purposes` said last; named means including an auxiliary control valve for admitting con'ipressed air into said duet at intervals and exhausting air therefrom at. atmosphere at other intervals for the purpose described.

T. ,ln two c vcle Diesel .engines of the ported cylinder typer` piston controlling means to scavenge th(` working chamber with air after each working stroke of the piston. said means including a scavenging valve and a duct leading theretfn means to inject a spray of fuel oil into the compression space of the. engine after the scavenging air is comilnesscd therein by the` piston` and means associated with the aforesaid parts for operating the engine under compressed air for starting purposes. said last, named means including an auxiliary control valve for admitting compressed air into said duet at in- 'lemals and exhausting air therefrom to atmf sphere at other intervals, and manually controlled shifting means to render said auxiliary control \alve operative and said fuel and scavenging valve non-operative and vice versa.

S. ln tiwo cycle internal combustion engines having piston controlled exhaust and hiv-pass ports and ducts, a Cylinder head, a scavenging valve in said head to deliver air t'rxni the b v--pass into the working chamber, means causing the working piston to draw a fresh air charge into itself on one stroke and deliver it compressed to the ley-pass duet on another stroke and again compressing the air in tue worting chamber, a fuel valve on the head vfor injecting fuel into the coinpreszscd air within the compression space of the tngine and an auxiliary valve eonneeted with the hjikpaes duct for delivering coinpresscd starting air at times, means to perate said fuel and scavenging valves and said auxiliary valve7 and means to render said vhiel and scavenging valves non-operative while said auxiliary valve is operative and 'vico versa, said valve operating means including` circular ciunt'crbalances on the h .sha oll the engine. cam elements on said comiterhalances and rocker arms eonncced with said valves and associated with sail cani elements.

t). ln internal combustion engiiies having a cylinder with a working chamber, a Cylii. er head unit comprising a body having a transwrsely elongated narrow compression ,space extending :a des thc width ol' the working chamber` said compression spaceJ being centrally enlarged. said head having a fresh air duct terminating in a portr in the central enlargena-ut. of said compression space and provided with a valve scat, a valve iciated with said :feat and carried by the clvliudcr head body` said cylinder head body having a fuel porti in its side wall at one end of said elongated compression space and a fuel injection valve carried bv the head hotly to deliver thi` fuel into the compression space transversely.

i LlUNAlD V. UOSFORD.

DAVID DVISON. 

